1. Field of the Invention
This invention relates to high melt strength, high impact resistant polycaprolactam compositions, containing aminoalkyltrialkoxysilane compound, a process for producing same and products made therefrom.
2. Brief Description of the Prior Art
Although polyamide molding compositions and other polymers having low melt strength values have met with a high degree of commercial success, they are generally not used for applications where a particular melt strength is required, such as in blow-molding processes to produce bottles or other relatively heavy duty containers.
U.S. Pat. No. 3,673,155 (June 27, 1972) describes bis(aminoorganosilyl)hydrocarbon-modified polyamides useful as molding compounds and insulating film. However, the reference does not describe compositions, useful in blow molding applications, which have high melt strength.
U.S. Pat. No. 3,341,501 (Sept. 12, 1967) describes linear polyamide compositions having organosilane end groups, which can be bonded to glass or metal with a tenacity that withstands boiling water. However, the reference does not describe polyamide compositions having high melt strength which are useful in blow-molding applications.
There is a need in the art to modify polyamide compositions, particularly polycaprolactam having a low melt strength value, in such a way as to improve both its melt strength as well as its stability at elevated temperatures. Potential markets for blow-molded polycaprolactam have not been effectively developed owing to the fact that the melt strength of conventional polycaprolactam compositions is not high enough for practical blow-molding operations. In view of its low melt strength, conventional polycaprolactam compositions, even with close temperature control, form parisons lacking in integrity which have a tendency to neck-in. These parisons do not widen, whereas parisons prepared from materials having high melt strength, such as polyolefins, swell and drop easily over the blow pin in a blow-mold operation.
Therefore, polycaprolactam compositions having high molecular weight, high tensile strength, and capable of being blow-molded into relatively large heavy duty containers, are not presently commercially available.